contemplate

look at thoughtfully; observe deep in thought; "contemplate one's navel"

consider as a possibility; "I contemplated leaving school and taking a full-time job"

think intently and at length, as for spiritual purposes; "He is meditating in his study"

reflect deeply on a subject; "I mulled over the events of the afternoon"; "philosophers have speculated on the question of God for thousands of years"; "The scientist must stop to observe and start to excogitate"